Magnetic hoisting apparatus



Nov. 20, 1962 E. H. BICK MAGNETIC HOISTING APPARATUS 2 Sheets-Sheet 1 Filed June 19, 1961 A flame] Nov. 20, 1962 E. H. BlcK 3,064,843

MAGNETIC HOISTING APPARATUS Filed June 19, 1961 2 Sheets-Sheet 2 a I he 3 I j b O \l 30 .2

l l I l l l l l l I-m I l llVVE/VTOR EDWARD H. B/CK A'fforney 3&54343 Patented Nov. 20, 1962 fiice MAGNETIC HOISTENG APPARATUS Edward H. 'Bick, Joliet, lit, assignor to United tates 'Steel'Corp'oration, a corporation of New Jersey Filed June 119, 1961, See. No. 118,064 3 Claims. (Cl. 214-623) The present invention relates generally to material handling equipment and more particularly has as its primary object the provision of an improved magnetic hoisting apparatus especially suitable for transferring bulk magnetic articles such as ferrous nails from a lowerlevel loading station to an upper level discharged station.

It is another object of my invention to provide an improved transfer chute and pick-up device arrangement in a magnetic hoisting apparatus 'of the type having an electromagnet incorporated in the pick-up device which is mounted for movement along a vertical path between the lower-level loading station and the upper-level discharge station.

It is a further object of my invention to provide an improved transfer chute and pick-up device arrangement of the foregoing character wherein the transfer chute is pivoted at its upper end at substantially the same level as the discharge station and is pivotal upwardly through an angle of less than 90 degrees from an inoperative vertical position out of the path of the pick-up device to an operative transfer position lying under the pick-up device when the latter is at the discharge position.

As a corollary to the object immediately above, it is a further object of my invention to provide a transfer chute and pick-up device arrangement of the foregoing character wherein the transfer chute is not connected with the pick-up device but is adapted to be pivoted to operative position by the pick-up device as the latter approaches the discharge station.

It is still another object of my invention to provide a transfer chute and pick-up device arrangement of the foregoing character wherein the electromagnet of the pick-up device is supported by a lost-motion mounting so that when the electromagnet is brought to rest on a surface it is rendered self-adjusting vertically relative to the pick-up device.

It is a further object of my invention to provide a transfer chute and pick-up device arrangement of the foregoing character wherein the amount of articles to be picked up by the electromagnet can be controlled.

These and other objects will become more apparent after referring to the following specification and attached drawings, in which:

FIGURE 1 is a front elevational view;

FIGURE 2 is a vertical sectional view taken on the IIII of FIGURE 1; and

FIGURE 3 is a perspective view of the electromagnet mounting of the invention.

As the apparatus of my invention comprises similar conjointly operative mechanisms respectively arranged on opposite sides of the vertical center line of the apparatus in opposed relation to each other, the following description, for convenience, is more specifically directed to the mechanism on the left hand side of the apparatus as viewed as in FIGURE 1. However, it is to be under stood that the description is equally applicable to the line corresponding parts of the mechanism on the right hand side of the apparatus which are designated by the same reference numerals but with the addition of a prime It will of course be appreciated that because of their disposition on opposite sides of said center line certain of the parts will be made as rights and lefts or otherwise oppositely formed.

Referring more particularly to the drawings reference numeral 2 designates an upstanding rectangular box-like frame within which are mounted two pairs of spaced vertical guide rods 4, 4 and 4, 4. A pair of pick-up devices, designated respectively by reference numerals 6 and 6', are slidably mounted one on each pair of guide rods for movement in a vertical path between a lowerlevel loading station A and an upper-level discharge station B. I V 7 On the top of the frame 2 are mounted -a reversible drive motor 8 and a drive shaft assemblyconsisting of a shaft 10 having a sprocket 12 and two cable sheaves 14 and 14 mounted thereon. Motor 8 is connected to shaft 19 by means of a sprocket l6 fixed on the shaft of the motor and a chain 18 which is trained around the sprockets 12 and 16. The pick-up device 6 is alternately raised and lowered between stations A and B by means of a cable 29 which is affixed by one end to the pick-up device and wound about the sheave 14 at its other end. The raising and lowering of the pick-up device is accomplished by reversing motor 8. h v

A feeder chute 22, welded or otherwise rigidly mounted on the frame 2, is disposed below the level of the discharge station B centrally of the frame 2 for feeding articles to equipment (not shown) located adjacent the frame 2. A transfer chute 24 is pivotally mounted by its upper end on the side of the frame 2 by means of a pivot shaft 26 which is affixed to the underside of the chute and has its ends carried in bearing collars 28 which are bolted to the frame 2. A pair of spaced parallel arms 39 project at right angles from the upper end of the transfer chute 24 and normally extends toward the path of travel of the pick-up device 6 when the transfer chute is in inoperative vertical position as shown at the right in FIGURE 1.

When the pick-up device 6 is raised from station A to station B, striker arms 32, a pair of which is affixedto and projects laterally from the pick-up device, engages the arms 30 of the transfer chute 24 and pivots the transfer chute upwardly through an angle of less than degrees to an operative transfer position in which it is 'angula rly inclined in a downward direction from the pivot shaft 26 and disposed under the pick-up device, as shown at the left in FIGURE 1. Lowering the pick-up device from station E to station A allows the transfer chute 24 to dropby gravity to its vertical inoperative position out of the path of the pick-up device. A resilient stop 34 may be provided on the side of the frame 2, as best shown in FIGURE 1, for absorbing the im pact of the transfer chute when it drops to inoperative position.

The pick-up device 6 includes a bracket 36 which is slidably mounted on and extends between the. pair of guide rods; 4, 4. An electromagnet 38 is carried by the bracket 36 by means of a lost-motion connection or support in such a manner as to be self-adjusting with respect' to its vertical position as it comes to rest on a surface, as will become apparent hereinafter. The support for the electromagnet consists of a cross-bar 40 with vertically positioned guide rods 42 aflixed to the ends thereof. Guide sleeves 44, afiixed to bracket 36 over suitable openings therein, receive guide rods 4-2 and thus establish a sliding connection between the bracket 36 and the electromagnet 38. Collars 46 and a cross bar 48 are secured to the upper ends of the guide rods 42 and serve as stop means to limit the downward travel of the electromagnet 38 with respect to the bracket 36. In operation, the sliding connection which is aiforded between the bracket and the electromagnet permits the electromagnet to come to rest on a mass of nails N Within a hopper P disposed in the bottom of the frame 2 at the loading station A and automatically adjust its level relative to the bracket 36 which is free to complete its downward travel as governed by the fixed length of cable 20. This arrangement places only the weight of the electromagnet and the supporting elements connected therewith on the mass of nails and tends to prevent the creation of an undesirable cavity or depression in the mass of nails and also prevents cocking of the bracket 36 on the guide rods 4.

The nails N may be supplied to the loading station by a chute C which deposits the nails on a raised central distributing surface S from which they slide into the hoppers P and P.

Electric current for the electromagnet is supplied by a cable 50 which is automatically reeled and unreeled by a spring-loaded reel 52. The flow of current to the electromagnet is controlled by a rheostat 54. The shell or casing for the electromagnet 38 is made of non-magnetic material such as copper or non-magnetic stainless steel so as to eliminate residual magnetism after the electromagnet is de-energized.

In operation, to transfer nails N contained in hopper P to feeder chute 22, motor 8 is actuated and the'electromagnet which is positioned within the hopper is energized simultaneously so as to attract the nails thereto at the instant the electromagnet starts its upward travel. As the pick-up device carrying the loaded electromagnet moves upwardly it automatically moves the transfer chute 24 into operative transfer position as explained above. When the upwardly moving pick-up device reaches discharge station B, as shown at the left in FIG- URE 1, it engages and trips a limit switch 56 which is disposed adjacent the upper end of the path of travel of the pick-up device. Both limit switches 56 and 56' are connected with the motor 8 and the electromagnets 38 and 38' so that tripping of either switch causes simultaneous reversal of motor 8, de-energization of the electromagnet which is in position at station B, and energization of the electromagnet which is in position at station A. When the loaded electromagnet at station B is de-energized, the nails fall from the electromagnet onto the transfer chute 24 therebelow and from there onto the feeder chute from whence the nails pass to equipment (not shown) located adjacent the frame 2. The non-magnetic casing of the electromagnet eliminates residual magnetism which would cause the nails to cling to the face of the electromagnet after it has been de-energized. As one electromagnet is being lowered toward its position at station A in the hopper P, the other electromagnet is being raised toward discharge station B. The amount of nails picked up by each electromagnet may be closely controlled by controlling the flow of current to the electromagnet by means of the rheostats 54 and 54'. This. control arrangement is particularly advantageous when the apparatus of the invention is used in a nail packaging line.

Itwill be understood that, if desired, the apparatus of the invention may be limited to a single electromagnetic pick-up device rather than the dual arrangement shown.

' The apparatus of the invention has been illustrated and described as used for handling nails, however, it will be understood that the apparatus is not restricted to such use but may be used for handling other magnetic bulk articles of similar nature.

The apparatus described may be operated manually or may be provided with suitable controls for automatic operation. Such controls are well known to those versed in the art and, therefore, have not been shown.

It should now be apparent that I have accomplished the objects initially set forth. I have provided an improved magnetic hoisting apparatus especially suitable for transferring magnetic articles from a lower level to an elevated feeder chute. The improved magnetic hoisting apparatus of the invention includes an electromagnet of variable strength and a transfer chute movable from an inoperative vertical position out of the path of the electromagnet to an operative transfer position lying under the electromagnet and inclined downwardly toward the feeder chute when the electromagnet is positioned in discharge position above the feeder chute. The transfer chute of the invention pivots upwardly through an arc of less than degrees in moving from its inoperative to its operative position. Thus, operation of the transfer chute between inoperative and operative position requires less space between the loading discharge positions of the electromagnet than was required heretofore in magnetic hoisting apparatus.

The transfer chute of the apparatus of the invention is not directly connected with the pick-up device of the apparatus but is provided with arms which are engageable by striker arms projecting from the pick-up device as the latter moves upwardly. When the arms of the chute are engaged by the striker arms the transfer chute is pivoted from inoperative to operative position. Since the transfer chute is pivoted at substantially the same level as the discharge position of the electromagnet, the transfer chute is pivoted to operative position as the electromagnet reaches its discharge position.

In the improved magnetic hoisting apparatus of the invention 1 have provided a lost-motion mounting for the electromagnet so that when the electromagnet is brought to rest on a surface the electromagnet is rendered vertically self-adjustingso that only the weight of the electromagnet and its mounting will bear on the surface.

While one embodiment of my invention has been shown and described, it will be apparent that other adaptations and modifications may be made without departing from the scope of the following claims.

I claim:

*1. In a bulk article handling apparatus of the type having a pick-up device mounted for movement along a vertical path betwen a lower article pick-up position and an upper article discharge position the improvement therewith of a pair of spaced vertical guide rods, a bracket extending between and mounted on said guide rods for vertical movement between said pick-up position and said discharge position, an electromagnet depending from said bracket, a lost-motion connection between said elec tromagnet and said bracket, a transfer chute having a pivot connection at its upper end mounted for pivotal movement in an upward direction from an inoperative vertical position out of the path of movement of said bracket to an operative transfer position in which it is angularly inclined in a downward direction from said pivot connection and disposed under said electromagnet when said bracket is in said article discharge position, a pair' of spaced parallel arms projecting at substantially right angles from the upper end of said transfer chute, said arms extending toward the path of movement of said bracket when said transfer chute is in its said inoperat1ve vertical position, and striker means projecting laterally from said bracket and adapted to engage said pair of arms during upward movement of said bracket to thereby pivot said transfer chute from its said inoperative vertical position to its said operative transfer posinon.

2. Apparatus as defined in claim 1 including a. casing of non-magnetic material around said electromagnet.

3. Apparatus as defined by claim 1 in which said lostmotion connection includes a pair of spaced upright sleeves on said bracket, said bracket having an opening therethrough communicating with each of said sleeves, a pair of spaced guide rods projecting upwardly from said electromagnets, each of said guide rods extending slidably through one of said openings and one of said sleeves with a portion thereof projecting upwardly of its re- 6 spective sleeve, a collar on the projecting portion of each of saidlast-narned guide rods for limiting the movement thereof relative to its respective sleeve, and a cross-bar attached to and extending between said collars.

References Cited in the file of this patent UNITED STATES PATENTS 2,733,824 Ruppe Feb. 7, 1956 

